1. Field of the Invention
The present invention relates generally to a disk drive, and more particularly to a disk drive designed to prevent contact of a disk and an actuator arm due to an external shock.
2. Description of the Related Art
In a conventional magnetic disk drive, there is case that an actuator arm or a spindle on which a magnetic disk is mounted that may be tilted to some extent by an external shock exerted on the magnetic disk drive. In such a case, the front end of the actuator arm comes closest to the magnetic disk, because the actuator arm is unusually flat in shape. Further, since the actuator arm is supported in a cantilever fashion, the amplitude of vertical vibration of the actuator arm due to the external shock is largest at the front end of the arm. Therefore, after experiencing the external shock, the tilt of the actuator or the spindle is associated with the vertical displacement of the actuator arm, resulting in a structure such that the front end of the actuator arm tends to come into contact with a data region of the magnetic disk.
In general, a magnetic disk drive sometimes receives an external shock while mounting it into a computer, carrying a portable computer in which the disk drive is built, etc. Therefore it is necessary to improve the external shock resistance of a magnetic disk drive. However, due to a recent decrease in the size of a magnetic head in response to a decrease in thickness and an increase in storage capacity in a magnetic disk drive, a magnetic head mounting height (the distance between an actuator arm and a magnetic disk) becomes as a result, as a result the allowable amplitude of vertical vibration of the actuator arm upon receipt of an external shock is reduced. Accordingly, when the magnetic disk drive receives an external shock, the front end of the actuator arm tends to come into contact with the magnetic disk surface, causing damage to the data region of the magnetic disk. Further, in many cases, a magnetic disk drive having a small number of magnetic disks adopts a single-supported spindle structure such that a spindle shaft is fixed to a base only, from a cost-reduction viewpoint. However, this structure is inferior to a double-supported spindle structure in that the spindle shaft it is more, causing a problem where the outermost circumferential portion of the magnetic disk tends to come into contact with the actuator arm facing thereto.
It is therefore an object of the present invention to provide a disk drive which can minimize the vibrations of the actuator arms and the disks when the disk drive receives an external shock, thereby preventing damage to the disks.
In accordance with an aspect of the present invention, a disk drive comprising a housing; a disk rotatably mounted in said housing and having a plurality of tracks; a rotating mechanism for rotating said disk; a head slider having a transducer for reading/writing data on said disk; and an actuator for moving said head slider across said tracks of said disk; said actuator comprising an actuator arm rotatably mounted in said housing; a suspension having a front end portion for supporting said head slider and a base end portion fixed to a front end portion of said actuator arm; and a pad mounted on a disk opposing surface of said actuator arm; said pad overlapping at least an outermost circumferential portion of said disk in a specific position of said actuator upon stoppage of driving of said disk drive.
Preferably, the pad is formed of resin or rubber, and overlaps a non-data region formed in the outermost circumferential portion of the disk. The thickness of the pad is set preferably smaller than the thickness of the head slider. By mounting the pad on the actuator arm, a clearance between the actuator arm and the disk at the outermost circumferential portion of the disk in a direction perpendicular to the disk surface"" can be reduced. Accordingly, even when the disk drive receives an external shock, the pad mounted on the actuator arm comes into contact with the outermost circumferential portion (the non-data region) of the disk, thereby limiting a tilt of the actuator or the spindle to prevent contact of the front end of the actuator arm with a data region of the disk.
In accordance with another aspect of the present invention, a disk drive comprising a housing having a base and a cover fixed to said base; a disk rotatably mounted in said housing and having a plurality of tracks; a rotating mechanism for rotating said disk; a head slider having a transducer for reading/writing data on said disk; an actuator for moving said head slider across said tracks of said disk; and a stopper fixed to said base, said stopper having a groove for receiving an outermost circumferential portion of said disk with a given vertical clearance.
In a disk drive wherein the actuator takes a rest position in the outermost circumferential portion of the disk upon stoppage of driving of the disk drive, a stopper for suppressing the vertical vibration of the actuator arm at the rest position of the actuator may be fixed to the base.
In accordance with a further aspect of the present invention, a disk drive comprising a housing; a disk rotatably mounted in said housing and having a plurality of tracks; a rotating mechanism for rotating said disk; a head slider having a transducer for reading/writing data on said disk; and an actuator for moving said head slider across said tracks of said disk; said actuator comprising an actuator arm rotatably mounted in said housing; a spacer fixed to a front end portion of said actuator arm; a suspension having a front end portion for supporting said head slider and a base end portion fixed to said spacer; and a pad provided on a disk opposing surface of said actuator arm at a position near said spacer.
Preferably, the pad is formed of resin or rubber, and the thickness of the pad is set smaller than the thickness of the head slider.
In accordance with a still further aspect of the present invention, a disk drive comprising a housing having a base and a cover fixed to said base; a spindle assembly having a shaft fixed to said base, a spindle hub rotatably mounted on said shaft, and a motor for rotating said spindle hub; a disk mounted on said spindle hub and having a plurality of tracks; a head slider having a transducer for reading/writing data on said disk; and an actuator for moving said head slider across said tracks of said disk; said spindle hub being integrally formed at its upper end with an annular projection; said cover having a circular recess for receiving said annular projection with a given horizontal clearance.
The above and other objects, features and advantages of the present invention and the manner of realizing them will become more apparent, and the invention itself will best be understood from a study of the following description and appended claims with reference to the attached drawings showing some preferred embodiments of the invention.